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<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>04_对象扩展</title>
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<body>
<!--
1. Object.is(v1, v2)
  * 判断2个数据是否完全相等
2. Object.assign(target, source1, source2..)
  * 将源对象的属性复制到目标对象上
3. 直接操作 __proto__ 属性
  let obj2 = {};
  obj2.__proto__ = obj1;
-->

<script type="text/javascript">

    console.log(Object.is('abc', 'abc'));//true
    console.log(NaN == NaN);//false
    console.log(Object.is(NaN, NaN));//true

    console.log(0 == -0);//true
    console.log(Object.is(0, -0));//false

    //Object.assign(target, source1, source2..)
    let obj = {name : 'kobe', age : 39, c: {d: 2}};
    let obj1 = {};
    Object.assign(obj1, obj);
    console.log(obj1, obj1.name);

    //直接操作 __proto__ 属性
    let obj3 = {name : 'anverson', age : 41};
    let obj4 = {};
    obj4.__proto__ = obj3;
    console.log(obj4, obj4.name, obj4.age);
  
  

</script>
</body>

</html>